Semiconductor device using SOI-substrate

Abstract

According to a feature of the present invention, a semiconductor device includes a SOI substrate, including a semiconductor substrate; an insulating layer formed on the semiconductor substrate and a silicon layer formed on the insulating layer. A drain region and a source region are formed in the silicon layer so that the source region is in contact with the insulating layer but the drain region is not in contact with the insulating layer.

1. A semiconductor device, comprising:
 a SOI substrate, including a semiconductor substrate; an insulating layer formed on the semiconductor substrate and a silicon layer formed on the insulating layer, wherein
 a drain region and a source region are formed in the silicon layer so that the source region is in contact with the insulating layer but the drain region is not in contact with the insulating layer. 
 
 
     
     
       2. A semiconductor device according to  claim 1 , wherein
 the insulating layer comprises a stepped region projected toward the source region.